Using ML to analyze Facebook posts
for this kind of ml training, you will need a ton of data first, at least in the thousands. If you have a bot program that fetches those data for you, AI is the way to go. I'm not sure how else you would do it though.

To train the nn you will need the inputs(the post) and the targets(the rating you want it to output). The targets could be anything you want, like the ratio of likes to views, etc.

There are tons of ML libraries out there and I recommend keras as it is easy to learn for beginners, hope it helps :)